Re: [PATCH] memcg: make threshold index in the right position
From: Kirill A. Shutemov <hidden>
Date: 2012-02-02 10:13:18
Also in:
linux-mm
On Thu, Feb 02, 2012 at 05:45:19PM +0800, Sha Zhengju wrote:
From: Sha Zhengju <redacted> Index current_threshold may point to threshold that just equal to usage after __mem_cgroup_threshold is triggerd.
I don't see it. Could you describe conditions?
quoted hunk ↗ jump to hunk
But after registering a new event, it will change (pointing to threshold just below usage). So make it consistent here. Cc: KAMEZAWA Hiroyuki <redacted> Cc: Kirill A. Shutemov <redacted> Signed-off-by: Sha Zhengju <redacted> --- mm/memcontrol.c | 7 ++++--- 1 files changed, 4 insertions(+), 3 deletions(-)diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 22d94f5..79f4a58 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c@@ -183,7 +183,7 @@ struct mem_cgroup_threshold { /* For threshold */ struct mem_cgroup_threshold_ary { - /* An array index points to threshold just below usage. */ + /* An array index points to threshold just below or equal to usage. */ int current_threshold; /* Size of entries[] */ unsigned int size;@@ -4319,14 +4319,15 @@ static int mem_cgroup_usage_register_event(struct cgroup *cgrp, /* Find current threshold */ new->current_threshold = -1; for (i = 0; i < size; i++) { - if (new->entries[i].threshold < usage) { + if (new->entries[i].threshold <= usage) { /* * new->current_threshold will not be used until * rcu_assign_pointer(), so it's safe to increment * it here. */ ++new->current_threshold; - } + } else + break; } /* Free old spare buffer and save old primary buffer as spare */-- 1.7.4.1
-- Kirill A. Shutemov